This invention relates to a low-pressure discharge lamp, and more particularly to a small-sized lowpressure discharge lamp which has a small distance between its cathode and its anode and which operates without any substantial anode fall voltage.
A single end type discharge lamp disclosed in Japanese patent application unexamined publications JP-A-58-42158 and JP-A-58-145055 is known as an example of a small-sized low-pressure discharge lamp having a small distance between its cathode and its anode.
The prior art low-pressure discharge lamp described above, was operated while continuously externally heating its cathode.
Due to the necessity for continuously externally heating the cathode in its steady state, the prior art low-pressure discharge lamp required two power supplies, that is, a cathode power supply and a discharge power supply. As another problem, the luminous efficacy of the prior art low-pressure discharge lamp was not high due to the necessity for continuously supplying cathode heating power from the cathode power supply.